Improving the Equipment Efficiecy (OMR Machine-A Case of Education Board Computer...

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Master of Advanced Engineering Management

Improvement in Equipment Efficiency: Case of

Education Board Computer Centre

By

SYED MD. SHAEEDUZZAMAN

This thesis has been submitted in partial fulfillment of the requirement for the degree of

Master of Advanced Engineering Management (AEM).

Department of Industrial and Production Engineering (IPE)

Bangladesh University of Engineering and Technology (BUET),

Dhaka-1000, Bangladesh.

December 2008

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The thesis titled – “Improvement In Equipment Efficiency: Case of Education

Board Computer Centre” submitted by Syed Md. Shaeeduzzaman, Roll No.

040408116P, Session April 2004 has been accepted as satisfactory towards partial

fulfillment of the requirement for the degree of Master of Advanced Engineering

Management on November 05,2008.

BOARD OF EXAMINERS

Dr. A.K.Masud

Associate Professor

Department of Industrial and Production Engineering

Bangladesh University of Engineering and Technology

Chairman

(Supervisor)

Dr. Abdullahil Azeem

Associate Professor



Member

Dr. Nafis Ahmad

Assistant Professor



Member


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DECLARATION

It is hereby declared that this thesis paper or any part of it has not been submitted

elsewhere for the award of any degree or diploma.

Syed Md. Shaeeduzzaman


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ACKNOWLEDGEMENT

This study would not have been possible without the support and guidance of my

project supervisor Dr. A.K. M Masud, Associate Professor, Department of IPE, BUET. I

would like to take this opportunity sincerely thank him for his valuable advice, constant

support and encouragement in completing the project.

My sincerest gratitude to all the individuals of EBCC, Dhaka, who directly or

indirectly helped me out in many instance through giving their precious time for

consultancy, who are always their provide support, ideas, their constructive criticism

towards my study.

I would also like to thank my respected teachers of the department, classmates,

friends and family members who directly or indirectly gave encouragement and support

in completing my job. In addition, I would be grateful to my Division Signal and Telecom

Engineer, Bangladesh Railway, Paksey, Pabna Mr. Asim Kumar Talukder. However, my

express thanks to all person of EBCC and Railway Subordinate of office member, Paksey

because at final moment of this job I joined in Bangladesh Railway getting a better

opportunity in my service from EBCC.


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ABSTRACT

Education Board Computer Canter (EBCC), a sister concern of all Education

Board’s of Bangladesh has been done Examination related jobs; e.g., registration

processing, coding of answer scripts, publication of result, certificate and transcript

printing etc. since 1994. EBCC use Optical mark reader (OMR) to achieve these aspects

for accurate, timely, and cost-effective data collection.

This study will briefly trace the problems in data collection process in EBCC. A

detailed explanation will be made of how EBCC are able to maximize their usage of

OMR with existing system by using prevailing method Total Productive Maintenance

(TPM). Also gives a straightforward scheme for the countermeasures of data collection

process using the Pareto analysis system by means of Why Why Because Logical

Analysis (WWBLA) techniques as well as exposed the improvement of Overall

Equipment Efficiency (OEE) of the process.


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-: TABLE OF CONTENTS:-

Page

No.

Chapter-1: Overview of Education Board Computer Center

1.1 Introduction 1

1.2 Objective of the Project 2

Chapter-2: Literature Review

2.1 Introduction 4

2.2 O.M.R System in Result Processing and Student Registration 4

2.3 Methodology of the case Study 5

2.3.1 Total Productive Maintenance 6

2.3.2 Overall Equipment Efficiency 8

2.3.3 Why Why Because Logical Analysis 8

Chapter-3: Education Board’s & EBCC

3.1 Introduction 9

3.2 History of the Education Board’s 9

3.3 Structure of the Education Board’s 10

3.4 Activities of the Education Board’s 10

3.4.1 Revenue and Expenditure 11

3.4.2 Human Resources of the Education Boards 11

3.4.3 School and College Administration 11

3.4.4 Rules of Business 11

3.5 Computer System in Public Examination Process 13

3.5.1 Organization Chart of EBCC 13

3.6 Activities of Education Board Computer Center (EBCC) 14

3.7 Disbursement of Education Board in favor of Computerized Result

Processing System

15

Chapter-4: Optical Mark Reader (OMR): Scanning System

4.1 Introduction 18

4.2 AXM- 995 OMR Specifications 18

4.3 Disposition of the parts of AXM-995 OMR 20

4.4 Application of Optical Mark Reader 22

4.5 Disposition of the OMR forms used in EBCC 23


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4.6 Data Processing System in EBCC 28

4.7 Scanning System in EBCC 30

4.8 Optical Mark Reader (OMR) - Problems and Errors 33

Chapter-5: Fault Analysis: Case Study

5.1 Introduction 37

5.2 Functions of TPM 37

5.3 The Advantages of TPM 38

5.3.1 TPM - TQM (Total Quality Management) Many Similarities 40

5.4 Generalized Losses of a manufacturing organisation 40

5.4.1 Addressing the Six Big Losses 42

5.5 Importance of Overall Equipment Effectiveness 43

5.5.1 OEE Factors 44

5.5.2 Calculating OEE 48

5.6 Identification the fault process of OMR scanning system 49

5.6.1 Check Sheet 50

5.6.2 Analytical Techniques of Fault analysis 54

5.6.3 Pareto Analysis 54

5.6.4 Cause Effect and Pareto Integration 55

5.6.5 Identification the significant Losses in OMR scanning System 55

5.7 Calculating OEE for OMR 57

5.7.1 Factors influence OEE in OMR Scanning System 58

5.7.2 The Stages of WWBLA 59

5.8 Results 64

Chapter 6: Conclusion & Recommendation 66

References 68


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LIST OF TABLES

Table 1: Scanning and related picture of EBCC in S.S.C Examination 2007

Table 2 : Scanning and related picture of EBCC in H.S.C Examination 2008

Table 3 :Shorting Expenses of S.S.C Examination 2007 & H.S.C Examination (in BDT)

Table 4:Scanning Expenses of S.S.C Examination 2007 & H.S.C Examination ( in BDT)

Table 5: General Technical Information of AXM 995 OMR

Table 6: Electrical Characteristics of AXM 995 OMR

Table 7: Mechanical Characteristics of AXM 995 OMR

Table 8: Dimensions of the Machine of AXM 995 OMR

Table 9: Printer Characteristics of AXM 995 OMR

Table 10: Replacement parts list of AXM 995 OMR

Table 11: Similarities and difference between TQM and TPM

Table 12: Generalized Losses of a manufacturing organisation

Table 13: Overall Equipment Efficiency Factor

Table 14: Representation World Class OEE Factor

Table 15: Period & Phase the OMR machine stop in study period.

Table 16: Pareto Chart for Six major Losses in OMR Scanning System

Table 17: Major Causes of machine stoppages

Table 18: Why Why Because Logical Analysis (WWBLA) worksheet.


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LIST OF FIGURES

Figure 1: Organization Chart of EBCC

Figure 2: AXM-995 OMR (Front End)

Figure 3: AXM-995 OMR (Back End)

Figure 4: AXM-995 OMR (Light Barrier Sensors)

Figure 5: H-type form

Figure 6: E-type form

Figure 7: SIF-type form (top side)

Figure 8: SIF-type form (bottom side)

Figure 9: M Type OMR form

Figure 10: P Type OMR form

Figure 11: Flow chat of Data Processing system in EBCC.

Figure 12: Flowchart of scanning system

Figure 13 : A Tag sheet used in EBCC

Figure 14: Impact of maintenance on competitiveness

Figure 15: Overall Equipment Effectiveness Model

Figure 16: Check sheet use for counting the No. of Time(s) the fault Occurred

Figure 17: Check sheet use for counting the Total Stopping Time (in Min.) of the OMR.

Figure 18: Pareto Chart for six major losses

Figure 19: WWBLA Overview

Figure 20: Pareto Chart for major causes of machine stoppage


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ABBREVIATIONS

EBCC Education Board Computer Center

SSC Secondary School Certificate Examination

HSC Higher Secondary Certificate Examination

BISE Board of Intermediate & Secondary Examination

OMR Optical Mark Reader

TPM Total Productive Maintenance

OEE Overall Equipment Efficiency

GOB Government Of Bangladesh

IT Information Technology

BISE Board of Intermediate and Secondary Education

SIF Student Information Form

MCQ Multiple Choice Questions

HEX Hexa Decimal Number

TQM Total Quality Management

NG Not Go

WWBLA Why Why Because Logical Analysis


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Chapter-1: Introduction

1.1 Introduction:

Education Board Computer Center (EBCC) is the sisters concern of eight educations

boards. All these autonomous bodies are functioning under a same platform, example of

which is the simultaneous result publication. Chairman of Dhaka Education Board

governs functionalities of it as an additional appointment and Senior System Analysts are

in charge of different boards. All the boards are combined here for security purpose and

to facilitate simultaneous jobs of result processing, to exchange ideas, views and

technologies directly. It acts as a bridge among the boards [1].

The Boards of Intermediate and Secondary Education including are responsible for

conducting the public examinations such as Secondary School Certificate (S.S.C) and

Higher Secondary Certificate (H.S.C) level public examinations. The Boards’ are also

responsible for the reorganization of the private sector educational institute.

To publish the result of S.S.C. and H.S.C. Examinations more correctly and fast,

Computer Center of Bangladesh University of Engineering and Technology (BUET) was

given the responsibilities of publishing the results of two public examinations in 1994 of

then four boards (Dhaka, Rajshahi, Comilla and Jessore) with computer technology using

coding mechanism and O.M.R. (Optical Mark Reader) technology. Then in 1995

Education Board Computer Center started its operation at Dhanmondi, Dhaka with the

own work force of respective boards. Now Dhaka Board, Rajshahi Board, Chittagong

Board, Madrasah Board, Barisal Board under Jessore Board and Sylhet Board under

Comilla Board are functioning at Computer Center.

Fast result publication of S.S.C. and H.S.C. Examinations of the boards, registration

processing, preparing admit card, tabulation sheet, transcripts and certificates and other

examination related jobs are done in this center. Here the operations are performed

through computerized system with the help of O.M.R. technology. Since commencement,

it has been publishing the result before the scheduled time and publishing the result in

international standard grading system of S.S.C. Examination since 2001 and of H.S.C.

Examination since 2003.


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Education Board Computer Center (EBCC) is the largest O.M.R. mechanism based

computerized setup for public examination perhaps in Asia. At present 34 high-techs,

O.M.R. machines are operating here. Moreover, it is coping pace with the fast changing

technologies in both software and hardware. EBCC is mainly an IT (Information

Technology) organization and its main structure based on OMR machine. Therefore, in

this case study efficiency improvement of OMR machine is regarding a crucial issue.

In today's fast-paced information-driven society, the need for accurate, timely, and

cost-effective data collection is very critical. Optical mark reader (OMR) systems can be

used to achieve these aspects. This case study describes the development of a low-cost

and high-speed OMR system for marking multiple-choice questions and related

arrangement. Effective mark detection and verification algorithms have been developed

and implemented to achieve real-time performance at low computational cost.

There are some identified problems while operating the OMR machines. That is why

the production target cannot achievable every time. The problems of OMR machine are -

Sheets are not accepted, unidentified sheet, Length error, Jam before head, Jam under

head etc. Those are being the faulty input material of OMR machine [2]. Productivity is

getting down due to improper use of production management. Lake of schedule

maintenance, continuous production also hampers [3].

Total Productive Maintenance (TPM) is a maintenance program, which involves a

newly defined concept for maintaining plants and equipment. The goal of TPM is

markedly increase production, while at the same time, increasing employee morale and

job satisfaction as well as increase the efficiency of the system. TPM [4] deals with the

tools and techniques, which help identifying and reducing equipment losses to

maximizing overall equipment efficiency (OEE) [5]. This study describes the

development on how the TPM tools and techniques can be applied in EBCC for

improving efficiency (OEE) of the OMR machine.

1.2 Objective of the Project:

To implement the IT (Information Technology) in all sectors of GOB

(Government of Bangladesh), at fast GOB is executing IT policy in the Education Sector.

On this way, GOB (Government of Bangladesh) was given the responsibilities of

publishing the results of S.S.C. and H.S.C. examinations more correctly and fast to the


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computer center of Bangladesh University of Engineering and Technology (BUET). In

1995, this job is assigned to EBCC. EBCC is committed to do all the job assign by the

authority timely, accurate and cost effective way. One of the technologies in common use

at EBCC is optical mark reading (OMR). Day by day, the area of business of EBCC is

increased with the change of IT (Information Technology). In addition, the OMR usage

has increased with the system. The need has arisen for additional user services support in

the areas of OMR documentation, education, utility programming, and office procedures.

Therefore, the efficiency improvement of OMR machine is a vital topic. On this concern

of the OMR process, the objective of thesis is following:

• To identify the different fault of the OMR process.

• Root cause analysis of the process.

• Pareto Analysis of the process.

• To improve quality of the process.

• To reduce production cost by means of reducing time loss.


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Chapter 2: Literature Review

2.1 Introduction:

Education Board’s objective is to provide quality service in Secondary and Higher

Secondary level of education specially in conducting examinations and to maintain the

standard of educational institutions. For these reasons, it introduced computerized system

in result processing and registration, international standard grading system, result

publication through website and so on.

An optical mark reader has a document feed hopper and several stackers. It works

with those documents, which are printed with mark positions on its specified areas. A

mark made in a position using a dark pencil or black ink is read by OMR. The OMR can

read about 10,000 documents per hour. It is a document reader and is commonly used for

quick evaluation of Multiple Choice Examination answer sheets [1].

2.2 O.M.R System in Result Processing and Student Registration:

EBCC is used OMR form for collecting data. Data is captured from compatible

scripts by scanning through O.M.R. (Optical Mark Reader) machine. There is no scope of

inaccuracy in information gathering. The forms are machine-readable where a student has

to fill up few circles to provide personal information (viz. name, father’s name, date of

birth, school/college code etc.). These filled circles are read through O.M.R. and

information is gained which makes the database.

In this method of mark recognition, a thin beam of light is directed on the surface

of the paper, which contains dark pencil, or black ink marks. Since the dark mark absorbs

comparatively more light than the surrounding area, it reflects laser light to the detector.

This reduction in reflected light helps to recognize the mark.

Answer script contains 31-digit special code called litho-code. Moreover, the

examiners when given for evaluation cannot recognize the script that to which student or

to which school/college it belongs to. Because the portion of the O.M.R. compatible form

containing student’s roll, registration and subject code is detached from the answer script

after the exam and sent to computer center. As the examiner cannot identify the student or


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institution of the answer script, student gets justification in evaluation. After evaluation

head examiner sends the second portion of O.M.R. readable form of the answer script to

the computer center. In this system, modern and practical oriented litho-code is used

which is a random code with 31 digits and unique for every scripts. This litho-code is

matched by computer software and the mark against a roll no. is got and thus tabulation is

made based on that. In computerized system, no data is entered manually. Each

information is entered by scanning through O.M.R. machine. Therefore, there is no scope

of mistake in information gathering and result processing. Result is published correctly

and fast by the present computer system. For this reason, students get opportunity to get

admission in colleges/universities timely, which helps to reduce session jam. There is no

session jam in S.S.C. and H.S.C. level.

2.3 Methodology of the case Study:

In this study, firstly all sections of the EBCC are pointed out for assessment. It is

observed that the goal of all factory improvement activity is to increase productivity by

minimizing input and maximizing output. Output refers not only to increased productivity

but also to better quality, lower costs, timely delivery, improved industrial safety and

hygiene and to a more a favorable working environment.

At this point equipment and machinery are the crucial factors increasing output.

Productivity, quality, cost and delivery, as well as safety, hygiene, environment, and

morale are all influenced significantly by equipment conditions.

The goal of maintenance management is to enhance equipment effectiveness and

maximize equipment output. It strives to attain and maintain optimal equipment

conditions in order to event unexpected breakdowns, speed losses and quality defects in

process. Overall efficiency, including economic efficiency is achieved by minimizing the

cost of upkeep and maintaining optimal equipment conditions throughout the life of

equipment. Therefore, the steps that were followed are:

• Identification of major losses

• Identification of significant losses by Pareto analysis

• Calculation of Overall Equipment Efficiency(OEE)

• Reduction of losses with analytical Techniques.


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At first, all the sections of EBCC are studied. Then it is identified and reduced

equipment losses to maximize overall equipment efficiency (OEE) by using the tools and

techniques of Total Productive Maintenance (TPM). From the different analytical

techniques used in TPM for improvement, here we used WWBLA (Why Why Because

Logical Analysis).

2.3.1 Total Productive Maintenance:

After the Second World War the Japanese Industry realized, that they must have a

higher quality in the products to compete on the world market. The Japanese companies

were importing the management and manufacturing technologies from the USA, and then

tailored them to their needs .To be effective in the maintenance their imported the concept

of the preventive maintenance from the USA for over 40 years ago. Later were also the

principles of the productive maintenance, the maintenance prevention and the reliability

engineering imported. The company Nippondenso co. was the first to start with the

productive maintenance , 1969 they introduced TPM , to meet the challenges in growing

amount of the automation and the new demands , the automation was creating to the

maintenance and to the whole company. In 1971, the same company got the first

“Distinguished Plant Prize “, given by the JIPM, Japanese Institute of Plant Maintenance

(Nakajima, 1988). To eliminate waste, Toyota became one of the first companies to

implement TPM Nakajima, 1988). Toyota measures six categories of equipment losses

throughout its production System [4]. These are (also Fredendall 1996):

• Equipment failures: Sporadic and chronic equipment failure / breakdowns

sudden and unexpected sporadic breakdowns are infrequent and result from the

deterioration of the mechanical and electrical operating components. For

example a hydraulic error in tool changer of the CNC - machine tool or an

electrical error in the CNC - control etc. Chronic breakdowns, which are the

result of the defects in equipment, tools, materials, and operating methods, occur

frequently, resulting in small amounts of lost time. For example, unpredicted

cutting tool breakdowns in the chip- breaking of difficult materials, mistakes in

the choice of the manufacturing methods etc.

• Setup and adjustment: Make-ready and equipment adjustments. With shorter

run lengths, smaller batches and more make-readies, reduction in make- ready

time and new job adjustments, emphasis is being placed on time - to - good


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counts. For example when a new job comes to a machine tool, tooling and

fixtures have to be changed.

• Idling and minor stoppages: Material abnormalities and slight machine

malfunctions that can be overcome by replacing materials or resetting press

components. For example, incoming material has not equal quality; the

automating tool changer is not working properly.

• Reduced speed: For example while numerous reasons are advanced for running

presses and bindery equipment at slower than rated speeds , less than label -

speeded operations represent a productivity loss .

• Defects in the process: Defective products, for whatever reason

must be treated as a loss and therefore eliminated. For example, dimensions a

dimension are not inside of the tolerance area. The products have some surface

damages etc.

• Reduced yield: start up losses. Start - up loss is lost time after the make-ready is

complete and production sheets / signatures are being counted, but at a reduced

speed. The losses are generally accepted as a process variable, but

account for considerable productivity loss [3].

These six losses are combined into one measure of overall equipment effectiveness

(OEE), which is:

OEE = Equipment availability x Performance Efficiency ×Rate of Quality Products

In the year, 1995 there were are about 800 companies or company units using the TPM in

Japan Johansson, 1996). In addition, the European companies have started to apply TPM;

one of the very first has been the Swedish car manufacturer Volvo in the Gent

factory in Belgium.

In Sweden especially the IVF (Institute for verkstadsteknisk forskning) has made

big efforts to implement TPM in the Swedish companies, also in the small - and medium

Sized enterprises.

2.3.2 Overall Equipment Efficiency:

OEE (Overall Equipment Efficiency) is a "best practices" way to monitor and

improve the efficiency of any manufacturing or operating processes (i.e. machines,


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manufacturing cells, assembly lines). OEE is simple and practical. It takes the most

common and important sources of manufacturing productivity loss, places them into three

primary categories and distills them into metrics that provide an excellent gauge for

measuring where we are - and how we can improve! OEE is frequently used as a key

metric in TPM (Total Productive Maintenance) and Lean Manufacturing programs and

gives you a consistent way to measure the effectiveness of TPM and other initiatives by

providing an overall framework for measuring production efficiency [5].

2.3.3 Why Why Because Logical Analysis:

WWBLA technique is a worksheet which identities the root causes of problem

[5]. In this technique, each major problem is considered separately and a worksheet is

prepared. For each problem, a cause is identified and called it first factor for problem.

Then it is verified whether it can be divided into further root causes. If it is possible, then

it is marked as G. Here, G stands for Go. Then a second factor for problem is identified is

verified. In this way, a third, fourth problems are identified. If it is not possible to identify

further, then verification is marked as NG (Stand for No Go). Finally, countermeasures

are identified for each causes of problem [6].


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Chapter-3: Education Board’s & EBCC

3.1 Introduction:

According to the ordinance of the board, The East Pakistan Intermediate and

Secondary Education Ordinance, 1961 (East Pakistan Ordinance No. XXXIII of 1961)

and its amendments No. XVI of 1962 and No. XVII of 1977, it is responsible for the

organization, regulation, supervision, control and development of Intermediate and

Secondary level public examinations and educational institutions.

3.2 History of the Education Board’s:

The Board of Intermediate and Secondary Education (BISE), Dhaka was

established on 7 May 1921 according to the recommendation of Sadler Commission.

Intermediate colleges and high schools in Dhaka city and Islamic intermediate colleges

and high Madrasah of greater Bengal were under control of that board. An advisory board

made by the director of public education department of greater Bengal was given the

governance of that board.

Dhaka Board was dissolved in September 1947 by a government order. Its name

was changed to ‘East Bengal Secondary Education Board’ in 1955 and it was live until

1961. Scope of this new board was limited to secondary level education of then the East

province of Pakistan and control of intermediate education was shifted to the University

of Dhaka.

Responsibility of intermediate education was given to the board from the

university in 1961 and board was named ‘Board of Intermediate and Secondary

Education, East Pakistan’.

In addition, after liberation it was named ‘Board of Intermediate and Secondary

Education, Dhaka’ with the scope of operation within Dhaka division. By the rise of

population of the country and to meet with the global change, government of Bangladesh

(GOB) has given deep look on education sector. To make easy of operation of the job

Govt. day by day increase the numbers of the education boards. At present Rajshahi,

Comilla, Jessore, Chittagong, Barisal, Sylhet and Madrasah the seven other education


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boards are working on the same fundamental policy of the first education board of the

country. Very soon a new education board namely Dinajpur Education Board is going to

start its journey with the same platform.

3.3 Structure of the Education Board’s:

All Boards of Intermediate and Secondary Education (BISE) are an autonomous

body and its business functions under the supervision of Ministry of Education of GOB.

The Chairman is the Chief Executive Officer of the board. The Chairman and eleven

members of different categories comprise a board committee approved by the ministry for

three (3) years, which is responsible for smooth functioning of the board.

Moreover there are several more committees formed according to ordinance and

related rules, viz.

(1) Academic Committee,

(2) Examination Committee,

(3) Disciplinary Committee,

(4) Finance Committee,

(5) Selection Committee,

(6) Regulation Committee,

(7) Appeal and Arbitration committee,

(8) Name and Age Correction Committee and so on.

3.4 Activities of the Education Board’s:

Preparation and arrangement of registration for students of class IX and XI for

two public examinations- S.S.C. and H.S.C. and result publication of those examination

within a specific duration. After publication of result of the two examination the

education board are distributed the tabulation sheet, academic transcript and certificate

among the students via schools and colleges. Reserving the interests of teachers’ jobs

through inspection of educational institutions, investigation, appeal and arbitration and

considering the extension of job of non-government qualified teachers. Inspecting newly

established educational institutions and giving approval, renewing approval, approving

the managing committee is of schools and governing bodies of colleges and permitting

the enrollment of students according to the government rules. Examination related overall

activities; viz. question papers preparation, revision, printing of question papers through


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B.G. Press, sending the question papers to the centers timely through respective Deputy

Commissioners with secrecy, distribution of answer scripts, which include O.M.R.

(Optical Mark Reader) compatible forms among examiners after the exam, and

arrangement of payment of remuneration of related teachers.

3.4.1 Revenue and Expenditure:

The education boards are a self-depended institution. Its sources of revenue are

examination, registration, permission, approval, renewal of approval, affiliation etc. The

Government of Bangladesh (GOB) approves the annual budgets made by the boards. It

takes no financial help from the GOB.

3.4.2 Human Resources of the Education Boards:

Chairman and some other top-level posts are filled up by the senior officers of

Education Cadre on deputation. Rest of the officers and employees are the own staff of

the board, job of which is regulated by the service rule of the boards. Number of officers

and employees are fixed based on the volume of responsibilities.

3.4.3 School and College Administration:

Permission for establishment of new schools and colleges (Private) and then

academic approval are given by the boards. Moreover, approval of managing committees

of schools and colleges, disposal of their disputes, inspection and supervision are few of

its important businesses.

3.4.4 Rules of Business:

To start a new school or college, application must be submitted to the boards four

months before the commencement of academic year defined by government. Fees of the

board have to be submitted in favor of Secretary of board through C.D. of Bank of each,

B.I.S.E. or Demand Draft respective Bank. No other mode of payment is accepted.

Attempts have to be taken to form new managing committee/governing body before

expiration date of managing committee/governing body and have to be submitted to board

within the scheduled time for approval.


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a) Age of student for enrollment in class IX is at least 12 (Twelve) years. Any

student successfully completing class VIII from any approved school can enroll in class

IX.

b) Generally direct (First) enrollment in class IX is not permissible. But if

anybody can show the certification of Headmaster of the relevant school that he or she

has acquired the knowledge equivalent to class VIII, can be enrolled in class IX within

the 31st March of the academic year with the special consideration and prior permission

of the education board.

c) Age of student for appearing in the S.S.C. Examination is at least 14 (Fourteen)

years on 1st January of the year of examination.

d) Student above 18 (Eighteen) years old cannot study in class IX and student

above 19 (Nineteen) years old cannot study in class X.

e) There is no age limit for studying in Higher Secondary level and for appearing

in the Higher Secondary Examination.

f) It is possible to appear in the H.S.C. Examination as an irregular (Private)

examinee three years after passing the S.S.C. Examination.

g) If any student, passed from foreign system is willing to enroll in class XI of any

approved college of Bangladesh, has to take prior permission from the Inspector of

Colleges of the board.

h) If any student passed from foreign institute (board, university) is willing to

enroll in class XI of any approved college of Bangladesh has to apply for equivalency of

his acquired degree in the board.

i) For opening any new subject in any school/college, taking prior permission

from the concerned department of the board is necessary.

j) Correction of Errors in Registration Card and Admit Card: A student has to fill-

up the O.M.R. readable SIF (Student Information Form) correctly after being admitted

into class IX and XI. Then he has the option to correct any errors scrutinizing the printout

copy. No application for change will be accepted after delivery of registration card and

admit card.


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3.5 Computer System in Public Examination Process:

Examination related jobs; e.g. registration processing, coding of answer scripts,

publication of result, certificate and transcript printing etc. have been done through

computerized system using O.M.R. (Optical Mark Reader) technology since 1994. For

these purposes, there is a combined computer center in Dhaka for all education boards

named Education Board Computer Canter (EBCC) at Dhanmondi. Chairman of any

Education Boards assigned by the Ministry of Education of GOB is in charge of it as an

additional duty.

3.5.1 Organization Chart of EBCC:

Early we mention that EBCC is the sister concern of Education Board. Now we

see the organisation chart of EBBC by the following diagram:

Figure 1: Organization Chart of EBCC

Chairman

Sr. System Analyst

System Analyst

Programmer Programmer

Asst. Programmer

Asst. Programmer Asst. Programmer Asst. Programmer

Operator Operator Operator Operator

Main. Engr.

Asst. Main. Engr.

Scanning Operator’s

Shorting Operators


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3.6 Activities of Education Board Computer Center (EBCC):

Information is gathered through O.M.R. scanning of S.I.F. (Student Information

Form) which is filled up by student and registration card is given. Computerized system

has eradicated the registration complicacies and fake registration problem. Timely

registration card distribution is possible in this system. Computerized admit cards are

given to registration cardholder authentic students to sit for the examination. List is made

to packet center-wise questions of S.S.C. and H.S.C. Examination, printed by B.G. Press,

based on the number of students.

Litho-code containing O.M.R. compatible form is enclosed with the answer script.

It contains three portions. First portion includes examinee’s roll no., registration no.,

subject code, second portion contains evaluated marks by the examiner for that script and

the third one has the evaluated marks and it is attached to the answer script. Three

portions of the top sheet contain same litho-code.

After the examination first portion of the answer script and M.C.Q. (Multiple

Choice Questions) answer script (Only for S.S.C. Exam.) which is also O.M.R.

compatible sheet are sent to computer center directly (with armed squad) or through

registered mail. Packets containing first portions of O.M.R. compatible forms are

received board-wise, sorted center-wise in computer sections of respective boards and

data is received by scanning through O.M.R. machines.

Marks for practical tests are also gathered through scanning of O.M.R. compatible

forms. Answer scripts evaluated and scrutinized by examiners/head examiners contain

marks in the second portion of the O.M.R. readable sheet, which is sent to computer

center by the head examiner by hand. Data is gathered by scanning the sheets. The

scanned data remains scattered.

The result is published through litho-code matching of the first portion containing

roll no., reg. no., subject code and the second portion bearing obtained mark. Tabulation

sheet is given within 7 (Seven) days of result publication. Transcript is given within 1

(One) month of result publication. Original certificate is provided within two months of

result publication. List of scholarships is prepared.


- 15 -

Besides the tasks mentioned above, it provides various types of information and

statistics as wanted by Ministry of Education, Directorate of Secondary and Higher

Education, BANBAIS, Education Board and different organizations.

3.7 Disbursement of Education Board in favor of Computerized Result Processing

System:

There is a fixed expense of EBCC excluding the remuneration and fixed asset cost

for the Computerized Result Processing System. Here we see the last two-job expense

detail of EBCC by the following tables[1]:

Table 1: Scanning and related picture of EBCC in S.S.C Examination 2007

Board Male

Student

Total OMR Form

Scanned Female Student

Total OMR Form Scanned

Total Script

Total Student

Dhaka 114523 4122821 107889 3884004 8006825 222412 Rajshahi 101009 3636310 93320 3359502 6995812 194328 Comilla 37023 1332828 35636 1282878 2615706 72659 Jessore 53456 1924423 47546 1711638 3636061 101002 Barisal 22712 817639 23360 840942 1658581 46072 Sylhet 13514 486511 14570 524502 1011013 28084 Chittagong

30376 1093529 28583 1028970 2122499 58958 Madrasha 55003 1980115 33654 1211544 3191659 88657

Total Examinee 7,23,514

Total Script/OMR from Scanned 2,60,46,497


- 16 -

Table 2 : Scanning and related picture of EBCC in H.S.C Examination 2008

Board Male

Student Total OMR

Form Scanned Female Student

Total OMR Form Scanned

Total Script

Total Student

Dhaka 81802 1963248 71926 1726224 3689472 153728 Rajshahi 72149 1731576 62213 1493112 3224688 134362 Comilla 26445 634680 23757 570168 1204848 50202 Jessore 38183 916392 31697 760728 1677120 69880 Barisal 16223 389352 15573 373752 763104 31796 Sylhet 9653 231672 9713 233112 464784 19366 Chittagong

21697 520728 19055 457320 978048 40752 Madrasha

39288 942912 22436 538464 1481376 61724

Total Examinee 5,61,810

Total Script/OMR From Scanned 1,34,83,440

Table 3 :Shorting Expenses of S.S.C Examination 2007 & H.S.C Examination

(in BDT)

Examination

Board S.S.C H.S.C Total

Dhaka 77500 5600 83100 Rajshahi 60000 4500 64500 Comilla 37500 2500 40000

Jessore 39000 3250 42250 Barisal 27000 2025 29025 Sylhet 30000 2250 32250

Chittagong 31250 2500 33750 Madrasha 52500 4500 57000

Sub Total 354750 Sub Total 381875 Grand Total 736625


- 17 -

Table 4: Scanning Expenses of S.S.C Examination 2007 & H.S.C Examination (in BDT)

Examination

Board S.S.C H.S.C Total

Dhaka 2402047 110684 2512731.6 Rajshahi 2098743 96740.6 2195484.12 Comilla 784712 36145.4 820857.24

Jessore 1090818 50313.6 1141131.96 Barisal 497574 22893.1 520467.48 Sylhet 303304 13943.5 317247.48

Chittagong 636750 29341.4 666091.08 Madrasha

957498 44441.3 1001939.04

Sub Total 8771447 Sub Total 9175950 Grand Total 17947397.00


- 18 -

Chapter-4: Optical Mark Reader (OMR):

Scanning System

4.1 Introduction:

In the market several types of OMR is available. At EBCC out of thirty-four OMR

machines twenty-five nos. are the model of AXM 995 and the other nine nos. are the

model of AXIOME- 880. In this case, study in EBCC AXM -995 types OMR machine

was taken as sample machine. The AXM 995 has been designed in compliance with the

European IEC safety and electronics regulations for data processing devices and in

compliance with safety regulations applicable to terminals in office equipment

environment. The machine can be used in permanent operation at office temperature.

4.2 AXM- 995 OMR Specifications:

The following tables give the total over view of AXM -995 OMR [2]:

Table 5: General Technical Information

Operation Temperature: +10 to +35 degrees centigrade Relative Operation humidity 20% to 80% without condensation Storage Temperature -10 to +50 degrees centigrade Relative storage humidity 5% to 9 % Voltage 50/60HZ 115V/230V (±10%) Network Filter Delta EMI interference filter. Power Consumption 100VA

Table 6: Electrical Characteristics

Microprocessor 80c85 CMOS RAM Program memory 32KB for interpretative routine RAM data memory 32KB. Saving to Ram 3V (Lt-In) Motor Stepper Motor 3Nos. Interface Serial V24/RS 232C.


- 19 -

Table 7: Mechanical Characteristics

Capacity of the input lift ~ 550 documents (for 90gm/m2 ) Capacity of the output trays Refused =~70 documents

Accepted= ~400 documents (for 90gm/m2 ) Speed of document transport 14 m/s or about 7200 doc. A4/h Paper weight 80 to 160 g/m2 Paper dimension 86 × 54 mm (minimum)

305 × 229 mm (maximum) Tray management Controlled by the program

Table 8: Dimensions of the Machine

Length: 715mm Width 435 mm Depth 390 mm Weight: 35 Kg.

Table 9: Printer Characteristics

Type of Head 9 needle matrix Character set Alphanumeric. Max. number of Chars. Per doc. 120 Characters. Printing Speed 40 cm per second.

Table 10: Replacement parts list:

Transport wheel 13 Separation Wheel 1 Separation rubber kit 1 Mini pitch belt 475×¼” and 390×¼ 2 Feeding belt 1 Fuse 1.6A and 3.15 A 2 Data cable DB 25 female / male 1 Adapter DB9 fem/DB 25 male 1 Ink ribbon LC9 1


- 20 -

4.3 Disposition of the parts of AXM-995 OMR:

1. Selector Switch

2. Start Button

3. Sixteen Character display unit

4. Separation Button

5. Feed Tray

6. Adjuster of document width

7. Selector of document width

8.Refused Tray

9. Adjuster of false document tray.

10.Output Tray

11. Hinged Cover including the printer option

12. Selection zone of True and False document

13.Optical Reading Head

Figure 2: AXM-995 OMR (Front End)

1. Main Power Switch

2. General Fuse

3. Power Plug

4. Parallel Plug

5. Serial Connector

Figure 3: AXM-995 OMR (Back End)


- 21 -

1. LB. A Controls if there are documents in the

input tray for automatic feeding

2. LB. B Detects a document before it passes under

the read head

3. LB. C Controls the document transport and

detects if the lower output tray is full. The reader

display will indicate GOOD TRAY FULL.

4. LB. D Controls the document transport and

detects if the upper ejection tray is full. The reader

display will indicate BAD TRAY FULL.

Figure 4: AXM-995 OMR (Light Barrier Sensors)

The Optical Mark Reader AXM 995 is an automatic device with a motorized

feeding tray and two output trays for the document. Its conception provided easy use and

access to documents and requires little maintenance. Its high transportation speed and the

unique feeding system make it a particularly secure and efficient device. Its programming

possibilities make it flexible, user friendly and easy to integrate into any data system.


- 22 -

4.4 Application of Optical Mark Reader:

There are different types of OMR machines. Optical Mark Reading (OMR)

technology is to process larger volumes of information faster and with greater accuracy.

They eliminate the need for manual data entry and collection by processing thousands of

documents an hour, automatically. What’s more, the variety of forms our scanners can

accommodate is almost limitless. Listed above are just some of the many applications our

scanners are used for. The small footprint, lightweight yet durable design and versatility

of the OMR make it an ideal device for a wide variety of data gathering applications:

• Retail Counters: Points of sale, Workstations

• Medical applications: Doctor orders, lab reports, patient visits, health risk

appraisal

• Education: Test scoring, multiple-choice examination forms

• Game: Gaming windows, betting houses

• Lottery, survey, ballot processing, voting booths, polling centers

• Kiosks and other remote locations, when coupled with a laptop computer, etc.

• Staffing/Employment: Job Knowledge Tests, EEOC and Civil Service Tests,

Employment Applications, Drug Testing and Tests, Employee Record Keeping,

• Benefits and Compensation: Time and Attendance (Payroll) ,COBRA ,Enrollment

and Change Forms, Benefit Evaluation Forms, United Way , Tuition Assistance,

Stock Purchase/401(k) Options

• Health and Safety: Safety Training/Testing, Hazardous, OSHA Compliance,

Communication Training, Response Forms, Health Risk Appraisals

• Training and Development: Skills Assessment Forms, Certification Testing,

Opinion and Organizational, Instructor Evaluation Surveys, Course Enrollment,

Technical Training Programs, and Attendance.


- 23 -

4.5 Disposition of the OMR forms used in EBCC:

1. Timing Mark

2. Page Head

3. Bullet Mark

4. Litho Codes

Figure 5: H-type form

The above OMR form is known as H-Type form in EBCC. The HEX code of 31

characters, 1 character of Board identity, 3 character of Subject code, 4 character of

Examiner Code, 4 character of answer script serial, 1 character of answer script extra paper

identity, 3 character of mark identity, 3 character of Head examiner mark identity data is to

collected from the form. The data file also given the identity of bullet mark. The bullet

mark represent from feed accurately or not.

1. Timing Mark

2. Page Head

3. Bullet Mark

4. Litho Codes

Figure 6: E-type form

The above OMR form is known as E-Type form in EBCC. The HEX code of 31

1

2

3

4

4 3

1

2


- 24 -

characters, 1 character of Board identity, 1 character of Examination identity, 3 character

of Subject code, 6 character of Student Roll No., 6 characters of Student Registration No.

data is to be collected from the form. The data file also given the identity of bullet mark.

The bullet mark represent from feed accurately or not. This two from are matching by

HEX Code.

This is a double

headed form. By

this form a Student

all information for

registration of S.S.C

& H.S.C are

collected. In Name

(40 Characters) ,

Student

Examination Board

(1 Character),

Passing Year ,Roll

No.& Registration

No. (6 Characters)

respectively, and

similar data which

mention in the

figure is collected.

Figure 7: SIF-type form (top side)


- 25 -

Figure 8: SIF-type form (bottom side)

This is back portion of the previous form. The mention list data are collected from

the sheet. Data accuracy also be collected by Bullet Marks. This can be feed by the OMR

machine by any way, but the programming language can be represented the data in

sequence.


- 26 -

Figure 9: M Type OMR form

This form knows as M -Type OMR in EBCC. This type OMR form is widely used in

various types of recruitment examination. The form is designed based on the other forms

using the, Timing Mark, Page Head, Bullet Mark etc. In EBCC, this form is used only in

S.S.C examination.


- 27 -

Figure 10: P Type OMR form

Several types of from are used in EBCC for different categories of data collection.

To design a new from and to read by machine is possible in form Timing mark & page

Head are designed in the same manner.


- 28 -

4.6 Data Processing System in EBCC:

Data collection procedure and result publication procedure of Education Board’s

of Bangladesh is done by EBCC. The entire procedures are shown by the following flow

chart diagram: ---

Figure 11: Flow chat of Data Processing system in EBCC.

The operation of EBCC is started when the OMR form is going on hand to the

students. The students first fill up the forms according to their respective information. The

False Data

OMR form fill up by the student

Send the OMR form to EBCC

Shorting

Scanning the OMR forms

Humidifying the OMR forms

Making Primary Database

Solve the database

Making Secondary Database

Making Final Database

Tabulate the database

Result

Manually Checked Data

Decoding

Scanning

Sorting


- 29 -

schools, colleges or examination centers authority collected the OMR forms and make the

packet. The respective authority then send these document to EBCC for taking further

action. The computer centre team then collected the all documents, which are coming to

their address from all corners of the country.

The first stage of data processing of EBCC is called shorting. In this stage

operator of EBCC is open the packet of OMR forms as well as the make a record both a

hard copy and a soft copy of the OMR forms. In the document the identity of the OMR

forms, i.e. numbers of forms with the schools, colleges or examination centers is

recorded. As the forms mainly arrival to EBCC by postal department it takes few days for

delivery. However, the forms are thin and packed a two or more thousand lots; so that

was untidy. These types of forms are making disturb while given to OMR machine for

feeding. To rectify these problems the lots of OMR forms are passing through a hot air

flow by the humidifier machine.

The third and the vital stage of data processing is the scanning. Our case study

mainly based on this stage. In this stage, the forms are feed by OMR machine. The

information of the OMR forms is recorded as text document by machine and its related

software through data cable.

The documents then converted as database information. From this data, error and

true data are marking separate. The true data are taking for further procedure. The false

data are sending to previous stage once for checking more consciously. Later the

information is repeated for previous action and after that, which was doing the further

procedure with the true data. Finally, all the data are proceeding for final action.

When the finished data is generated, the data is transferred for validation. In the

validation, stage each student all data are checked by means of all hidden codes by

software. In addition, the final data is captured as database in the format of Hexadecimal

number.

Later the data is used for preparing the tabulation. From the tabulated data, the

result is prepared. Before the result all, the data is stored in different database file in

Hexadecimal code. In addition, the respective files are keeping very in secret by

password. Only the chief executive of the respective education boards is the authority to

use the password. This stage is known as decoding in EBCC.


- 30 -

4.7 Scanning System in EBCC:

Before time we mention the major task in EBCC is the scanning section. We

choose this section as our case study. The entire scanning system is shown in the

following:

Press Start Button of OMR

Sort out OMR From

Preparation for data scanning

Software Loading in OMR machine

Enter File Name

PC

OMR

Manually ADD OMR form

Data Storage in PC

Stop the Program

Start another file

Stop the Process

Switch on PC & OMR

Figure 12: Flowchart of scanning system.

Start Scanning OMR Sheet

False OMR Sheet/Machine Stop


- 31 -

The entire scanning system by OMR machines shows in above figure 9. The files

are created in the from text file with an extension of (“X” “SUB” “T” “NUM”.doc). Here,

“X” first character of respective education board,

“SUB” subject code of the script,

“T” script category,

“NUM” number of the file created.

Each file contains 1000 / 1200 (One thousand / One Thousand two hundred)

sheets of data or very near to the same. A bundle has more or less five to six examination

center/ Examiners’ a single or multiple lots. Each files document are recoding in a

summarized method that is know as tag (Figure 10) in EBCC. If any queries of any

sheets are come for checking, the tag paper works as the hard copy of the data. Therefore,

tag paper is an important hardcopy document when the total data is prepared. In early

hours, we mention a bundle has more or less five to six examination center/ Examiners’ a

single or multiple lots; that is for searching a single sheet from a huge group of OMR

forms. Different logic programs use to purify the data. That is mention in next chapter 4.

The authority of center / Examiners’ mention the OMR forms information in a prescribed

format, along to the bundle. All this information is sequentially written down in tag sheets

(figure 13).


- 32 -

Board of Intermediate and Secondary Education, DA/RJHI/JSR/CMA/SLY/CTG

SSC/HSC Examination, 200X

File Name : X/ ### /$/ ###

Serial No.

Centre /Head

Examiner Code

Total Sheets in the

Bundle

Ending Sheet Roll/ Serial No.

Cum. Count of the sheet

Actual Total

Repeat Counting

Reject Number

of Document

D/C

01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20

OMR Machine No.

Solve Date:

OMR Operator & Date: Backup Date

Figure 13 : A Tag sheet used in EBCC


- 33 -

4.8 Optical Mark Reader (OMR) - Problems and Errors:

There are different problems and errors are showing while operating OMR machine.

Those errors are stopping the machine. Therefore, the machine operator should have a

deep look on the machine while it is running. On the time while error messages are

displayed ones’ should first remove errors of the machine and then again restarting the

machine. The common problems and errors are following:

• Sheets not accepted

There may be many reasons why sheets are not accepted by the OMR machine. If the

OMR forms are crumpled, in any way, the machine may give an error message and the

operator of the machine may need to restart the machine by removing the particular

problem. When sheets are not accepted by the OMR, the following error message may

shows in the display unit of AXM -995 OMR.

Bad Feeding: After three consecutive feedings of OMR sheet when the next OMR form

has still not arrived under light barrier LB B (2nd no. sensor) of the machine, the mention

error message showing in the display unit. The machine operators then replace the first

document (s) on the lift and press the start button of the OMR machine.

Jam Before head: The OMR form has reached on the light barrier LB B, but not the OMR

read head, the mention error message showing in the display unit. The machine operators

then remove the document having caused the paper jam. This document has not been read

correctly and should be put into tray of refused documents or back on the lift (input tray

of OMR) and press the start button of the OMR machine.

Jam Under head: The beginning of the OMR form has been detected by the OMR read

head, but its end has not been seen within a lap of one second of the document’s

appearance under the head, the mention error message showing in the display unit. The

machine operators then remove the document having caused the paper jam. This

document has not been read correctly and should be put into tray of refused documents or

back on the lift (input tray of OMR) and press the start button of the OMR machine.

Paper Press: While the document is not detected on the input lift in test mode, the

mention error message showing in the display unit. The machine operators then replaced


- 34 -

new document on to the input tray of the machine and press the start button of the OMR

machine.

• Operating Error

There may be many reasons while OMR forms are available on the input tray of machine

but the running OMR machine is stopping. Those problems of AXM -995 OMR is

following:

Bad Tray full: The OMR machine has two trays –one called good tray and the next one is

bad tray. In the continuous form has been detected by the OMR read head, but its end has

not been seen within a lap of one second of the document’s appearance under the head,

the mention error message showing in the display unit. The machine operators then

remove the document having caused the paper jam. This document has not been read

correctly and should be put into tray of refused documents or back on the lift (input tray

of OMR) and press the start button of the OMR machine.

Good Tray full: While the machine is continuously operating but the read OMR form,

fulfill the good tray i.e. there is not enough space to accepted next document must be

ejected, the mention error message showing in the display unit. Also if the light barrier

LB C (3rd sensor) is obstructed by any means then the machine also stopping displaying

this error message. All documents of the good tray should be removed and press the start

button of the reader.

• Unidentified sheet

If a MCQ form/sheet is fed in upside down or back to front as well as the OMR form

definition does not compare with the load software of the AXM-995 then this error will

be displayed on the PC.

• Length error

There may be many grounds while OMR forms are available on the input tray of machine

but the running OMR machine is stopping. Those problems of AXM -995 OMR is

following:


- 35 -

Sheet too short: The last transported OMR document in the machine is 6.25% shorter

than the reference document (usually the first document of a stack). Remove the

document having caused the error and press the start button of the reader to make the

machine restart.

Sheet too thin: The AXM-995 has a capability to read the 80 gms paper. The OMR sheet

which is now entering is more than 25% too thin. Remove the document having caused

the error and press the start button of the reader.

Sheet too thick: The OMR sheet, which is now entering, is more than 50% too thick.

Remove the document having caused the error and press the start button of the reader

Sheet too long: The last transported document is 6.25% longer than the reference

document (usually the first document of a stack).Remove the document having caused the

error and press the start button of the reader.

• Miscellaneous Error:

There are also some identified problems but those occur very few in the life period. Some

problem permanently stopping the machine and some may takes many to time to restart

the system. Those are being mentioned below:

Low Battery: The OMR motherboard battery of machine is empty and must be changed to

restarting the machine.

Bad Retention: The memory retention of the OMR is faulty; the battery could be defect.

Reload firmware and the application program of the machine to restart.

Path Not Free: Two documents are transported too closely to each other to the machine.

Remove the second document and press the start button on the reader. The removed

document has not been read.

No Black Gauging: The black reference of the synchronization (clock) mark sensor

varies. If the message returns after the reader has been switched off call on the

maintenance service.


- 36 -

No Decoder: If during the READ of OMR form or in BARCODE test the barcode option

is not there or defect, the reader will display NO DECODER. Firstly installed the barcode

software and restart the machine.

Probl Bac Appel: The input tray (lift) could not move up. Make sure nothing blocks the

movements of the input tray and press the start button. If the message returns call the

maintenance service.

Good Tray Error: The tray of accepted documents could not move up. Make sure nothing

blocks the movements of the tray and press the start button. If the message reappears, call

the customer service.

Security Stop: The security of the input tray (lift) is activated. Remove the fingers or

documents from the input tray and press the start button. If the message reappears, call

the maintenance service.

No Sheet in Good: The OMR form, which should be ejected to the tray of good OMR

forms, did not arrive Look for the document in the tray of refused OMR forms. This

OMR form has been read correctly. Press the start button to start the machine.

No Sheet In Bad: The OMR form, which should be ejected to the tray of refused OMR

form, did not arrive look for the document in the tray of accepted OMR forms. Press the

start button to start the machine.


- 37 -

Chapter-5: Fault Analysis: Case Study

5.1 Introduction:

Data collection and processing of the true data is the main job of EBCC. In the

case of entire processing of S.S.C / H.S.C examination result is completed by 60 (sixty)/

65 (sixty-five) working days. Total system of the result processing is already shown in

Figure 8. The entire system has dependent on four sections:

§ Sorting

§ Scanning

§ Validation

§ Decoding.

The major job of EBCC is done by scanning sections and the job is based on

OMR machine. Besides first two sections are working more or less simultaneously and

required about 45 (forty-five) to 50 (fifty) working days to complete. Moreover, the rest

two sections complete the final job within the rest stipulated time. Therefore, in case of

EBCC we use TPM for improvement the entire result processing system. We give a deep

observation on the OMR machine scanning system for better time management. In

addition, we are applying WWBLA as analytical instrument.

5.2 Functions of TPM:

A great amount of organizations finds, that in spite of the huge improvements in

the productivity in the last years, there is still a big potential to be better in utilizing the

machine tools and in reaching the better productivity goals. Like the Japanese say, “To

discover the mountain of possibilities “. One main method to meet this challenge is the

TPM. TPM is a systematic approach to understanding the equipment's function, the

equipment's relationship to product quality and the likely cause and frequency of failure

of the critical equipment components.

According to Japanese scientist Nakajima and Suzuki,” A formal definition and

concept is given by:


- 38 -

1. TPM is aimed at maximizing equipment effectiveness through the optimization

of equipment availability, performances, efficiency and product quality.

2. TPM establishes a maintenance strategy (level and type of PM, productive

maintenance) for the life of the equipment.

3. TPM covers all departments such as the planning department, the users and the

maintenance department.

4. TPM involves all staff members from top management down to shop floor

workers.

5. TPM promotes improved maintenance through small group autonomous

activities.

5.3 The Advantages of TPM:

A systematic and long - term work with the TPM has an influence especially on

the following elements in any organisation

• Productivity is improving through fewer losses in the company

• Quality is also been improved as a result, that the failures and malfunctions are

reduced and the order and method are focused

• The Costs are lower, because the losses, and other not value generating work

are reduced

• The Delivery Times can be kept better, because the production without

disturbances is easier to plan

• Environment and Security is better, because leakages are tightened.

• Motivation is higher, because the responsibility and rights are delegated and

the investment in the personal is done, in the form of education.


- 39 -

Total Available Time on Equipment Six Big Losses Overall Equipment

Effectiveness

Capabilities Competitive

Factors

Down Time Losses

Speed Losses

Defect Losses

Availability

Performance Efficiency

Equipment Failure

Setup and Adjustment

Idling & Minor Stoppage

Reduced Speed

Defects in Process

Reduced Yield

Rate of Quality Products

First Changeover Capability

Reduced Buffer Inventory

Increased Effective Capacity

Less Scarp and rework

Delivery

Flexibility

Cost

Quality

Decreased Lead Time

Figure 14: Impact of maintenance on competitiveness


- 40 -

5.3.1 TPM - TQM (Total Quality Management) Many Similarities:

The TPM program closely resembles the popular Total Quality Management

(TQM) program. Many of the tools such as employee empowerment, benchmarking,

documentation etc. used in TQM are used to implement and optimize TPM. The final

goal is to deliver a product, which is filling all the quality requirements of the customer,

and that all the costs can be predicted. It can be said, that the maintenance and the quality

are two different features of the same issue. So, that the maintenance is long - termed

quality control. The maintenance is concentrating on the machine, processes and slow

trends; meanwhile the quality control is dealing with tools, wear - off and the

management of fast changes.

Table 11: Similarities and difference between TQM and TPM

Category TQM TPM

Objective Quality(output and effects) Equipment (input and cause)

Means of attaining

goal

Systemize the management. It is

software oriented

Employees participation and it is

hardware oriented

Target Quality for PPM Elimination of losses and wastes

5.4 Generalized Losses of a manufacturing organisation:

One of the major goals of TPM and OEE programs is to reduce and /or eliminate

the losses of what are called the Six Big Losses – the most common causes of efficiency

loss in any manufacturing or simply any organisation which have a job on similar to

production. The following table lists the six big losses, and shows how they relate to the

OEE loss categories.


- 41 -

Table 12: Generalized Losses of a manufacturing organisation

Six Big Loss Category

OEE loss Category

Event Examples

Comment

Breakdowns Down time loss

Tooling failures

Unplanned maintenance

General Breakdowns

Equipment failure

There is flexibility on where to set the threshold between a breakdown (down time loss) and a small stop (speed loss).

Setup and adjustments

Down time loss

Setup/changeover

Material shortages

Operator shortages

Major adjustments

Warm-up time

This loss is often addressed through setup time reduction programs.

Small stops Speed loss Obstructed product flow

Component jams

Misfeeds

Sensor blocked

Delivery blocked

Cleaning/checking

Typically only includes stops that are under five minutes and that do not require maintenance personnel

Reduced speed Speed loss Rough running

Under nameplate capacity

under design capacity

equipment wear operator

inefficiency

Anything that keeps the process from running at its theoretical maximum speed (a.k.a. Ideal run rate or nameplate capacity).

Startup rejects Quality loss Scrap

Rework

In-process damage

In-process expiration

Incorrect assembly

Rejects during warm-up, startup or other early production. May be due to improper setup, warm-up period, etc.

Production Rejects Quality loss Scrap Rework In-process damage In-process expiration Incorrect assembly

Rejects during steady-state production.


- 42 -

5.4.1 Addressing the Six Big Losses:

The six big losses are and some of the events that contribute to these losses, we can

focus on ways to monitor and correct them. Categorizing data makes loss analysis much

easier, and a key goal should be fast and efficient data collection, with data put to use

throughout the day and in real-time.

• Breakdowns:

Eliminating unplanned down time of any plant is essential to improving OEE. Other

OEE factors cannot be addressed if the process is down. It is not only important to know

how much down time your process is experiencing (and when) but also to be able to

attribute the lost time to the specific source or reason for the loss (tabulated through

reason codes). With down time and reason code data tabulated, root cause analysis is

applied starting with the most severe loss categories.

• Setup and adjustments:

Setup and adjustment time is generally measured as the time between the last good parts

produced before setup to the first consistent good parts produced after setup. This often

includes substantial adjustment and/or warm-up time in order to consistently produce

parts that meet quality standards. Tracking setup time is critical to reducing this loss,

together with an active program to reduce this time (such as an SMED - single minute

exchange of dies program). Many companies use creative methods of reducing setup

time including assembling changeover carts with all tools and supplies necessary for the

changeover in one place, pinned or marked settings so that coarse adjustments are no

longer necessary, and use of prefabricated setup gauges.

• Small stops and reduced speed:

Small stops and reduced speed are the most difficult of the six big losses to monitor and

record. Cycle time analysis should be utilized to pinpoint these loss types. In most

processes, recording data for cycle time analysis needs to be automated since cycles are

quick and repetitive events that do not leave adequate time for manual data logging. By

comparing all completed cycles to the ideal cycle time and filtering the data through a


http://www.oee.com/oee_factors.html

http://www.oee.com/overall-equipment-effectiveness-glossary.html



- 43 -

small stop threshold and reduced speed threshold the errant cycles can be automatically

categorized for analysis. The reason for analyzing small stops separately from reduced

speed is that the root causes are typically very different, as can be seen from the event

examples in the previous table.

• Startup rejects and production rejects:

Startup rejects and production rejects are differentiated, since often, the root causes are

different between startup and steady state production. Parts that require rework of any

kind should be considered rejects. Tracking when rejects occur during a shift and/or job

run can help pinpoint potential causes, and in many cases, patterns will be discovered.

Often a six sigma program, where a common metric is achieving a defect rate of less than

3.4 defects per million "opportunities", is used to focus attention on a goal of achieving

"near perfect" quality.

5.5 Importance of Overall Equipment Effectiveness:

Many organizations that recognize the important roll equipment and process

performance have on bottom line results are turning to the measure, which drives TPM

called Overall Equipment Effectiveness (OEE), which incorporate not only availability

but also performance Rate and Quality Rate. In other words, OEE addresses all losses

caused by the equipment: not being available when needed due to breakdowns or setup

and adjustment losses; not running at the optimum rate due to reduced speed or idling and

minor stoppage losses; and not producing first A1 quality output due to defects and

rework or start up losses. A key objective of TPM is to cost effectively maximize Overall

Equipment Effectiveness through the elimination or minimization of all losses. A simple

model outlining these losses is shown in figure 15.

When many organizations first measure OEE it is not uncommon to find they are

only achieving around 40 %-60% (batch) or 50%- 75% (continuous process) whereas the

international best practice figure is recognized to be +85% (batch) and 95% (continuous

process) for Overall Equipment Effectiveness. In effect, this means there exists in most

companies the opportunity to increase capacity/productivity by 25%-100%. TPM

significantly reduces operational and maintenance costs by focusing on the root cause of

failure through the creation of a sense of ownership by the plant & equipment operators,

maintainers and support staff to encourage “prevention at source”. To understand the




- 44 -

thinking behind TPM we need to investigate what causes failure. Most of the concept of

the root cause of failure and the too used to assist in the search for the root cause

WWBLA.

5.5.1 OEE Factors:

OEE factor denotes the plant's efficiency and effectiveness as well as the overview of

productivity losses that occur in the typical manufacturing environment. Therefore, the

OEE calculation starts with plant operating time and end up at fully productive time,

showing the sources of productivity loss that occur in between the entire process. The Six

Big Losses describes the most common causes for efficiency loss usually found in

today's manufacturing environment. Six root causes of loss are presented, each directly

related to an OEE Factor. Here we have given detail concept of measuring the OEE of

any organisation.


http://www.oee.com/oee_six_big_losses.html

http://www.oee.com/oee_six_big_losses.html

- 45 -

• Plant Operating Time:

The Plant Operating Time is the subtraction of the category of time called Planned

Shut Down to actual operating time; which includes all events that should be excluded

from efficiency analysis because there was no intention of running production (e.g.

breaks, lunch, scheduled maintenance, or periods where there is nothing to produce). The

remaining available time is your Planned Production Time.

Overall Equipment

Effectiveness

Availability

Performance Rate

Quality Rate

Break down

Setup and Adjustment

Reduce Speed

Idling and Minor Stoppage

Defects and Rework

Startup

Six Big Losses Target

Zero

Minimize

Zero

Zero

Zero

Minimize

Figure 15: Overall Equipment Effectiveness Model


- 46 -

• Planned Production Time (Shut down Time):

OEE begins with Planned Production Time and scrutinizes efficiency and

productivity losses that occur, with the goal of reducing or eliminating these losses. There

are three general categories of loss to consider. Such as

i) Down Time Loss,

ii) Speed Loss and

iii) Quality Loss.

Availability takes into account Down Time Loss, which includes any Events that

stop planned production for an appreciable length of time (usually several minutes - long

enough to log as a track able Event). Examples include equipment failures, material

shortages, and changeover time. Changeover time is included in OEE analysis, since it is

a form of down time. While it may not be possible to eliminate changeover time, in most

cases it can be reduced. The remaining available time is called Operating Time.

• Operating Time (Down Time Loss):

Performance takes into account Speed Loss, which includes any factors that cause

the process to operate at less than the maximum possible speed, when running. Examples

include machine wear, substandard materials, misfeeds, and operator inefficiency. The

remaining available time is called Net Operating Time.

Net Operating Time:

Quality takes into account Quality Loss, which accounts for produced pieces that

do not meet quality standards, including pieces that require rework. The remaining time is

called Fully Productive Time. Our goal is to maximize Fully Productive Time. Here we

now give a look how the factors that contribute to OEE Losses are developed we can

quickly review the key points.


- 47 -

Table 13: Overall Equipment Efficiency Factor

Loss OEE Factor

Planned Shutdown - Not part of the OEE calculation.

Down Time Loss - Availability is the ratio of Operating Time to Planned Production

Time (Operating Time is Planned Production Time less Down Time

Loss).

- Calculated as the ratio of Operating Time to Planed Production

Time.

- 100% Availability means the process has been running without any

recorded stops.

Speed Loss - Performance is the ratio of Net Operating Time to Operating Time

(Net Operating Time is Operating Time less Speed Loss).

- Calculated as the ratio of Ideal Cycle Time to Actual Cycle Time, or

alternately the ratio of Actual Run Rate to Ideal Run Rate.

- 100% Performance means the process has been consistently running

at its theoretical maximum speed.

Quality Loss - Quality is the ratio of Fully Productive Time to Net Operating Time

(Fully Productive Time is Net Operating Time less Quality Loss).

- Calculated as the ratio of Good Pieces to Total Pieces.

- 100% Quality means there have been no reject or rework pieces.

• World Class OEE:

OEE is essentially the ratio of Fully Productive Time to Planned Production Time (refer

to the OEE Factors section for graphic representation). In practice, however, OEE is

calculated as the product of its three contributing factors:

OEE = Availability x Performance x Quality


http://www.oee.com/oee_factors.html

- 48 -

This type of calculation makes OEE a severe test. For example, if all three contributing

factors were 90.0%, the OEE would be 72.9%. In practice, the generally accepted

excellent goals for each factor are quite different from each other, as is shown in the

table below.

Table 14: Representation World Class OEE Factor

Worldwide studies indicate that the average OEE rate in manufacturing plants is 60%.

However, a World Class OEE is considered to be 85% or better.

5.5.2 Calculating OEE:

As early, we described the OEE calculation is based on the three OEE Factors:

Availability, Performance, and Quality. Now here is given the procedure how each of

these factors is calculated.

Availability

Availability takes into account Down Time Loss, and is calculated as:

Availability = Operating Time / Planned Production Time

Performance

Performance takes into account Speed Loss, and is calculated as:

Performance = Ideal Cycle Time / (Operating Time / Total Pieces)

OEE Factor World Class

Availability 90.00%

Performance 95.00%

Quality 99.90%

Overall OEE 85.00%


- 49 -

Ideal Cycle Time is the minimum cycle time that your process can be expected to

achieve in optimal circumstances. It is sometimes called Design Cycle Time, Theoretical

Cycle Time or Nameplate Capacity. Since Run Rate is the reciprocal of Cycle Time,

Performance can also be calculated as:

Performance = (Total Pieces / Operating Time) / Ideal Run Rate

Performance is capped at 100%, to ensure that if an error is made in specifying the Ideal

Cycle Time or Ideal Run Rate the effect on OEE will be limited.

Quality

Quality takes into account Quality Loss, and is calculated as:

Quality = Good Pieces / Total Pieces

And finally the OEE

OEE takes into account all three OEE Factors, and is calculated as:

OEE = Availability x Performance x Quality

5.6 Identification the fault process of OMR scanning system:

The OMR machine stops for different causes. For this reason, the data collection

time is required more. Our case study is to identification the major fault in scanning

system as well as to minimize the period of stopping OMR machines by means the

improvement of the Overall Equipment Efficiency (OEE).

Over the past 30 years, Japanese have studied and practiced what they term “Total

Quality Control” (TQC). One of the leaders in this movement has been Kaoru Ishikawa.

Ishikawa and others repeatedly point to fact that Japanese industrial workers are among

the worlds finest in their level of education and quantitative skills. Consequently, one of

the critical features of the Japanese approach to quality control is its focus on quantitative

methods on the factory floor.


- 50 -

Based on his experience in Japanese industry, Ishikawa states that as much as 95

percent of quality related problems in the factory can be solved with seven fundamental

quantitative tools, also termed the seven “old” tools. Those are:

a) Cause Effect diagram

b) Stratification analysis

c) Check Sheet

d) Histogram

e) Scatter diagram

f) Pareto analysis

g) Control charts.

In this study, I took the two tools. Check Sheet and Pareto analysis to identify the major

problem of the OMR scanning system in EBCC.

5.6.1 Check Sheet:

A check sheet is a simple tools used to record and classify observed data. There

are two types of check sheets (a) Pictorial and (b) tabular. Of the two different types, we

use a pictorial check sheet that shows in figure 16 & 17. The designed of the two check

sheets based on our demand as our case fault identification according OMR machine

history. One sheet is to count the no of time the fault occurs and the other sheet is to

calculate the time to rectify the problems.


- 51 -

Tag : Problem Check Sheet

Machine No. 13831 Operator Name: Md. Habibur Rahman

Date: 14/05/06 Script Type: H

Start Time: 12.15 p.m. Total Script: 1100

End Time: 12.34 p.m. Comments: Test Check

Error No. of Time(s) Occurred Total

Bad Feeding (BF) | 1

Jam Before Head (JBH) |||| |||| |||| 15

Jam Under Head (JUH)

Sheet too Thick (Stk)

Sheet too Thin (Stn) ||| 3

Sheet too long (Stl)

Good Tray Full (GF) | 1

Bad Tray Full (Btf)

Path Not Free(Pnf)

Security Stop (SS)

Lift Error (LE) | 1

Jam in Sorting (JIS)

Waiting Request (WR)

SOS test fail(SOS)

Paper Press (PP) |||| |||| |||| 14

Bad Retention (BR)

Other (OT)

Figure 16: Check sheet use for counting the No. of Time(s) the fault Occurred


- 52 -

Tag : Problem Check Sheet

Machine No. Operator Name:

Date: Script Type:

Start Time: Total Script:

End Time: Comments:

Error Total Stopping Time (in Min.) Total Time

Bad Feeding (BF) 1 1

Jam Before Head (JBH) 3 3

Jam Under Head (JUH)

Sheet too Thick (Stk)

Sheet too Thin (Stn) #

Sheet too long (Stl)

Good Tray Full (GF)

Bad Tray Full (Btf)

Path Not Free(Pnf)

Security Stop (SS)

Lift Error (LE) 2 1

Jam in Sorting (JIS)

Waiting Request (WR)

SOS test fail(SOS)

Paper Press (PP) 2 2

Bad Retention (BR)

Other (OT)

# Time required less than 1(one) minute.

Figure 17: Check sheet use for counting the Total Stopping Time (in Min.) of the OMR.


- 53 -

After studying all the sections of EBCC, the scanning sections were taken for the

case project purpose. Then all the scanning operators are informed about the case study

according to the TPM four steps policy. Three operators fill up the check sheet for fifteen

days in two sessions. From the check sheet, we summarized two categories of data for

our study purpose (Table 15). These figures denote the no times the OMR machines stops

during the case study period as well as represents the time the OMR machines shut down

for process operation.

Table 15: Period & Phase the OMR machine stop in study period.

Losses No. of times Shut down

( Causes of Machine Shut down ) Fault occurs period (in minute)

Bad Feeding (BF) 1486 22

Jam Before Head (JBH) 2642 27

Jam Under Head(JUH) 178 12

Sheet Too Thick(Stk) 141 2

Sheet Too Thin(Stn) 91 1

Sheet Too Long(Stl) 448 13

Good Tray Full(GF) 11 1

Bad Tray Full (Btf) 8 0

Path Not Free(PNF) 30 1

Security Stop (SS) 2 0

Lift Error(LE) 2 5

Waiting Request (WR) 2 0

SOS Fault(SOS) 0 0

Paper Press(PP)+Tag preparation +Bundle Packet 1280 100

Bad Retention(BR) 0 0


- 54 -

5.6 Analytical Techniques of Fault analysis:

Every organisation sets a preventing method of failure before it makes any harm.

There are several proactive tools, technique and quality method enables the

identification and prevention of process or product errors before they occur. The

common analytical techniques used in TPM for improvement a process is following [7] :

i)WWBLA

ii) P-M analysis

iii) Why Why analysis

iv) Fault tree analysis

v) Failure Mode Effect analysis

vi)Pereto analysis

vii)SPC etc.

5.6.1 Pareto Analysis:

In nineteenth century Italy, the Italian economist Vilferdo Pareto observed that

about 80 percent of the country’s wealth was controlled by about 20 percent of the

population. This observation leads to what is now known as the Pareto Principle; it is also

known as “80”-“20” rule. Popular scientist Juran and Gary applied this concept to the

causes of quality failures. They stated that 20 percent of the causes account for 80 percent

failures. In general, the Pareto Principle, applied to quality, suggests that he majority of

the quality losses are maldistributed in such a way that a “vital few” quality defects or

problems always constitute a high percent of the overall quality losses (but not in strictly

an 80-20 relationship)

The intent of a Pareto analysis is to separate that vital few from the trivial many.

Thus, the Pareto analysis can assist us to identify the most important effects and causes

and to stratify the available data so that we can prioritize our products –process

improvement efforts. In general, we see two types of Pareto diagrams: (1) result-category

diagrams and (2) cause-category diagrams. Results diagrams focus on the classification

and relative importance of observable results (e.g., product defect categories such as

scratches, dents). Cause diagrams focus on the classification and relative importance of

detected causes (e.g., process related categories such as a dull cutting tool, a misaligned

die).


- 55 -

5.6.4 Cause Effect and Pareto Integration:

Pareto analysis and Cause effect analysis are useful in all product life cycle

phases: definition, design, development, production, delivery, sales and service, usage

and disposal. They are systematic, through and based on simple logic. The Pareto

diagrams quantitative structure allows us to stratify and prioritize our information

(management by fact). The qualitative structure of the cause effect diagram allows us to

capture experience, engineering, judgment and reasonable technical speculation in our

results.

Pareto diagrams and cause effect diagrams analysis are frequently used together in

developing effective pro actions or corrective reactions since each provides different yet

necessary information to support the analysis. Typically, we use a Pareto analysis and the

resulting diagram to identify a critical problem or opportunity for quality improvement.

Then, we use the cause effect analysis and diagram to identify causes relative to the

effect.

The Pareto diagram helps determine the effect we select for the focus of CE

analysis. The cause effect diagram then displays all possible causes of a quality problem

or challenge and aids in identifying root causes. When the two diagrams are used

together, they become an instrument for documenting and communicating quality

improvement progress as well as for gaining perspectives on problem solving during the

quality improvement process.

5.6.5 Identification the significant Losses in OMR scanning System:

To identify losses and equipment efficiency of OMR scanning system in EBCC

we choose eight OMR machines for 6 days during operation. The data is representing in

Table 15 based on CE diagram. From these six (6) major losses, the most significant

losses are then identified by Pareto analysis.


- 56 -

Table 16 : Pareto Chart for Six major Losses in OMR Scanning System

Major Losses

Time (minutes) %Composition Cumulative % Paper Press (PP)

120 58 58 Jam Before Head (JBH)

29 14 72 Bad Feeding (BF)

25 12 84 Jam Under Head(JUH)

14 7 91 Sheet Too Long (Stl)

14 7 98 Lift Error (LE)

5 2 100

Total 207 100

The diagram is given below:

Therefore, by Pareto chart it is seen that the most significant sources of OEE

losses are Paper Press, Jam before Head and Bad Feeding of the OMR scanning system.

Pareto Chart for six major losses

0

20 40

60 80

100 120

140

Paper Press (PP) Jam Before Head (JBH)

Bad Feeding (BF) Jam Under Head(JUH)

Sheet Too Long(Stl) Lift Error(LE)

Tim

e

0

20

40

60

80

100

120

Cu

mu

lati

ve %

Figure 18: Pareto Chart for six major losses


- 57 -

5.7 Calculating OEE for OMR:

We know, OEE= Availability x Performance x Quality.

Again, Availability = Operating Time / Planned Production Time


Or, Performance = (Total Pieces / Operating Time) / Ideal Run Rate

Quality = Good Pieces / Total Pieces.

Here A, Running time per day =60 Minutes *7hrs=420 Minutes

B, Down time per day=30 minutes

C, Loading time per day=A-B=420-30=390 minutes

D, Stoppage losses per day=207/7=30 minutes

E, Operating time per day=C-D=390-30=360 minutes

F, Output per day = 2572 sheets

G, Rate of Quality Products=

(Processed amounts- Defect amount)/ Processed amounts*100

= (126000-5000)/126000*100=96.03%

[Defect amount =Error data/ Error Sheet]

H, Idle Cycle Time *=6 seconds =0.10 minutes

I, Actual Cycle time** =7 seconds=0.12 minutes

J, Actual Processing time^ =I*F=0.12*2572=309 minutes

K, Operating speed rate=H/I*100= (0.1/0.12)*100=83.33%

L, Net Operating rate=J/E*100=309/360*100=85.83%

M, Availability= (E/C)*100= (360/390)*100=92.30%


- 58 -

N, Performance efficiency=K*L*100=0.8333*0.8583*100=71.52%

* Ideally a machine read 50 sheets per minute

** Actually a machine read 40 sheets per minute

^ Per hour per machine output sheets= (126000/7)/7=2571.43,

So, OEE=M*N*G*100

=0.9230*0.7152*0.9603*100

=63.39%.

5.7.1 Factors influence OEE in OMR Scanning System:

From the Pareto chart six major fault breakdowns it is seen that the most

significant sources of OEE losses are Paper Press, Jam before Head and Bad Feeding of

the OMR scanning system. Early we mentioned that we use WWBLA to make out the

subdivision of major causes that break off the OMR scanning system efficiency.

From the case report, it is easily recognize that Paper Press is the vital issue of

machine stopping. In the case study, it is seen that the AXM -995 OMR trays can accepts

500 sheets at a time. Due to the post phase, scanning system software in EBCC

maximum 250 nos. sheet / OMR form with four (4) slots read in one interval for few

subjects. Moreover, most of the subjects OMR form scan with 100 nos. forms with 10 or

max 15 bundles. The operator records data in tag form as well as the bundle is packing

according to direction of EBCC. The properties of OMR machine gives use an idea that

30 sheets can read by the OMR machine in a minute. In practical, we see this is idle case.

Students have not adequate knowledge about the OMR form uses, therefore, the handle

the OMR with negligence. The unsafe carrying system of the OMR from far distance of

the country, Students negligence as well as the paper quality may the dent OMR form

that causes occasionally stopping the OMR machine in the fault name Jam before Head,

Bad Feeding etc. These causes of stopping OMR scanning system can call Idling and

Minor Stoppage. However, Idling and Minor Stoppage of the scanning system is the

combination of Paper Press (Tag preparation + Bundle packing), Jam before Head, Bad

Feeding. It can be easily observed from the following Pareto analysis.


- 59 -

Table 17: Major Causes of machine stoppages

Major Losses Time (minutes) %Composition Cumulative %

Tag preparation 49 35 35

Bundle packing 36 26 61

Jam Before Head 29 21 82

Bad Feeding 25 18 100

Total 139 100

From Figure 20, it is seen that the main cause of Idling and minor stoppage is Tag

preparation, Bundle packing, Jam before Head, Bad Feeding. Now WWBLA technique is

used for identifying the counter measures to reduce the problems.

5.7.2 The Stages of WWBLA:

Early we mention that in this study we used WWBLA techniques to identify the

root cause and then segment the root cause to solve the problem. A Why Why Because

Logical Analysis (WWBLA) starts with gathering information about the incident (Figure

15). This information is then used to construct either a List of Facts (facts listed alone) or a

Why Why-Because Logical List. When the first factor is identified then it is marked as G.

Here G means ‘Go”. The facts then divided into second factor for problem is identified

and verified. In this way, a third, fourth problems are identified. And so on. When the

factors are not segment to any factor, then it is marked as NG (stands for No Go). Finally,

countermeasures are identified for each root cause or facts of problem.


- 60 -

The entire process of WWBLA is factored into eight sub processes, Such that:

i) Gather Information (Root cause identification)

ii) Determine the Facts ( Segmentation of the root cause)

iii) Create a List of Facts ( create a list of related cause/problem of the process)

iv) Create a Why Because Logical List

v) Create an Auxiliary List of Facts

vi) Determine the Mishap / Top Node

vii) Determine the Necessary Causal Factors

viii) Quality Assurance and Correction of the WB Graph (Countermeasures

identified).

The total system can be represented by the following flow chart:


- 61 -

Incident occurred

Gather Information (GI)

Determine Facts (DI)

Clear picture of Course of events /

Participants?

Use list of facts

Create WWBLA

Correct WB-Graph

Determine Mishap / Top node (DM)

Assure Quality (AQ)

Create Auxiliary List of Facts (CA)

Create list of Facts (CL)

Finished

Create report

Determine Necessary casual factors

Figure 19: WWBLA Overview

Yes

No

No

Yes


- 62 -

In this study, we use check sheet to get information from the history of the OMR

scanning system in EBCC. As well as we used Pareto analysis to identified the major

losses in the total process. Here we used WWBLA to find out the segmentation the main

cause and to go its last stage for find the countermeasures. Here, each fault, which

interrupts the process, is known as facts and its division is known as Auxiliary facts. The

division of those facts is to identify the mishap and to set finalized countermeasures. Each

fact and consequently the auxiliary facts are verified whether it can be divided into

further root causes. If it is possible, then it is marked as G. Here, G stands for Go. Then a

second factor for problem is identified is verified. In this way, a third, fourth problems

are identified. If it is not possible to identify further, then verification is marked as NG

(Stand for No Go). Finally, countermeasures are identified for each causes of problem.

Pareto Chart for major causes of machine stoppage

0

10

20

30

40

50

60

Tag preparation Bundle packing Jam Before Head Bad Feeding

Figure 20: Pareto Chart for major causes of machine stoppage

Cu

mu

lati

ve

%

0

20

40

60

80

100

120

Tim

e


- 63 -

Table 18: Why Why Because Logical Analysis (WWBLA) worksheet.

Pro

ble

m

1st

Fac

tor

for

pro

ble

m

Ver

ific

atio

n

2nd

Fac

tor

for

Pro

ble

m

Ver

ific

atio

n

3rd

Fac

tor

for

pro

ble

m

Ver

ific

atio

n

Cou

nte

rmea

sure

s

1. Machine input tray is empty

G 1.1 Machine Operator is Busy

G 1.1.1 Operator is preparing Tag

NG 1.1.1. Tag should make from raw data using software.

2. OMR machine is wait for paper

G 2.1 OMR form is not placed accurately in the machine input tray.

G 2.1.1 Last OMR form is twisted / folding.

NG 2.1.1 Placed New OMR form / Smooth the twisted form and again placed the form.

3. OMR machine cannot take the form

G 3.1 Sheet thickness is not accurate

G 3.1.1 Two or more sheet is going to be feed

NG 3.1.1 Smooth the sheet or shuffling the sheets before placed in the machine input tray.

4. Machine is tried to take form but failed.

G 4.1 Adjust the Head of machine

G 4.1.1 Machine yet not takes the form.

G 4.1.2 Change the Transport wheel

NG. 4.1.2 Change the Separation wheel.

Pap

er P

ress

5. OMR form quality is poor

NG 5. Better quality of form should be used.


- 64 -

5.8 Results:

From the WWBLA worksheet, we found five segmentations against the paper

press fault in the OMR scanning System. Due to countermeasures found in the WWBLA,

the stoppage loss per day reduced to 30 minute to 26 minutes and consequently per

machine OMR form reading capacity almost increases from 2572 sheets to 3000 sheets

in an hour. According to the equation of OEE it is seen that if the countermeasures are

taken the losses per day can be reduced and hence OEE is increased which is shown

below:

OEE= Availability x Performance x Quality.

Again, Availability = Operating Time / Planned Production Time


Or, Performance = (Total Pieces / Operating Time) / Ideal Run Rate

Quality = Good Pieces / Total Pieces.

Here A, Running time per day =60 Minutes *7hrs=420 Minutes

B, Down time per day=20 minutes

C, Loading time per day=A-B=420-20=400 minutes

D, Stoppage losses per day=180/7=26 minutes

E, Operating time per day=C-D=400-26=374 minutes

F, Output per day = 3000 sheets

G, Rate of Quality Products=

(Processed amounts- Defect amount)/ Processed amounts*100

= (142000-4500)/142000*100=96.83%

[Defect amount =Error data/ Error Sheet]

H, Idle Cycle Time *=6 seconds =0.10 minutes


- 65 -

I, Actual Cycle time** =7 seconds=0.12 minutes

J, Actual Processing time^ =I*F=0.12*3000=360 minutes

K, Operating speed rate=H/I*100= (0.1/0.12)*100=83.33%

L, Net Operating rate=J/E*100=360/374*100=96.18%

M, Availability= (E/C)*100= (374/400)*100=93.57%

N, Performance efficiency=K*L*100=0.8333*0.9618*100=80.15%

^ Per hour per machine output sheets= (141850/7)/6=3000,

So, OEE=M*N*G*100

=0.9357*0.8015*0.9683*100

=72.62%.

Prior to apply WWBLA techniques we get OEE 63.39 %.


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Chapter 6: Conclusion & Recommendation

In the project work, it scrutinize that the two significant causes of losses that

decreases the efficiency of OMR machine, which Paper Press and Jam before head / Bad

are feeding. Of theses losses, the most significant loss Paper Press is considered for

reducing and thereby maximizing equipment efficiency. By WWBLA techniques, we

found five sections of the problems. We choose better OMR form, designed a sort

program against tag writing and used new separation and transport wheel, during the case

session. On this way, the OMR represent 9.23 % more efficient. Improve the OMR

machines OEE can improve as high as 85% or even more which is standard for Japanese

industries, if the entire root causes of significant losses are reducing.

EBCC may not think this matter earlier times i.e. because they have a loose

schedule time during this study period. However, this year GOB takes a policy to publish

the result of S.S.C and H.S.C examination within 60 (sixty) days. In this year to meet, the

schedule EBCC uses the machine more time. However, if they take the report as their

drug we are hopeful they can complete their job in the normal office time.

From the study, it is found that the concept of TPM can be applied to any industry

successfully. Today, with competition in industry at all time high, TPM may be one of the

tools that stand between success and total failure for some companies. It has been proven

a program that works. It can be adapted to work not only in industrial plants, but also in

construction, building maintenance, transportation and in variety of other situations like

EBCC. Employees must be educated and convinced that TPM is not just another

“program of the month” and that management is totally committed to the program and the

extended period necessary for full implementation. If everyone involve in a TPM

program does his or her part, and unusually high rate of return compare to resources

invested may be expected.

In the case study, it has been found that OEE has increased 72.62% from 63.39%

while a single problem was consider and analyzed by only one tool of TPM (WWBLA).

Here, it can also be mentioned that only one cause of the mentioned single problem has

been considered. Thus from the research work it can be concluded that the OEE could be

increased as high as to 85 %( which is a Japanese Bench Mark) if we consider all the


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problems and solve those by several analytical tools of TPM. Therefore, overall

performance of OMR machine can be improved by implementing TPM to EBCC for

meeting more jobs in a sort period in future.


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REFERENCES 1. (www.education board .gov. bd.) on 8.10.2007

2. Scantron Corporation, 1361 Valencia Avenue Tustin CA 92680, USA, User manual

AXM 995 OMR, April 1995.

3. Richard B. Chase, F. Robert Jacobs, Nicholas J. Aquilano, Operation Management

For Competitive Advantage, Tata McGraw-Hill Publishing Company Ltd, New

Delhi, 10th Edition 2004.

4. Venkatesh J, (www. plant –maintenance.com) An introduction to Total Productive

maintenance (TPM), The palnt Maintenance Resource Centre, Oct, 2005. Japan

Institute for Plant Maintenance, on 4.4.2007

5. (www.wem.nu/oee.html) OEE: Overall Equipment Efficiency, OEE index &

Calculation.

6. A practical Guide to Why Because Logical Analysis Method, Thilo Paul- Stuve,

September 21, 2005.

7. Creation of quality- Fundamental Strategic and Tactical Quality Tools, AIT,

Thailand.


http://www.education/

http://www.wem.nu/oee.html

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